import numpy as np
import matplotlib.pyplot as plt
plt.subplot(221)
x=np.arange(0,2*np.pi,0.01)
y=np.cos(x)
plt.plot(x,y)
plt.subplot(222)
plt.axis([-1,2,-1,2])
plt.axvline(x=0,ymin=0,linewidth=4,color='r')
plt.axvline(x=1.0,ymin=-0.5,ymax=0.5,linewidth=4,color='g')
plt.subplot(212)
x=np.arange(0,2*np.pi,0.01)
y=np.sin(x)
plt.plot(x,y)
plt.show()
